Traditional electronic door locks of the type typically used in hotel guest rooms do not effectively manage lock power consumption in a manner that compensates for open and closed conditions of hotel doors. As properly powered and functioning electronic locks are obviously critical to hotel operation, power supply to hotel door locks is always a concern. This concern is heightened in applications where power is at a premium, such as in the case of inductively powered door locks with only a small emergency battery. In these types of applications, power management that is specific to open and closed conditions of hotel doors is desirable.
Using inductively powered door locks as an example, when a door is closed (i.e. in the frame), inductively powered door locks have sufficient power available from induction to operate lock electronics. However, when a door is open, inductive power transfer ceases because the distance between transmitter and receiver in the inductive system exceeds the size of the corresponding magnetic field. With the lock operating in a normal manner during open conditions, a storage device disposed in the door lock that has been charged by inductive power transfer might be depleted at too fast a rate, particularly when a door is left open for a relatively long period of time (such as during room cleaning). If the storage device is depleted, the system necessarily falls back on the small emergency battery mentioned above. Fall back to the emergency battery is undesirable in that it could lead to a rapidly depleted battery, and thus a non-functioning lock. This may generate a need to equip the locks with more powerful batteries, and thus generate greater expense to the hotel.
However, an electronic lock of an open door obviously does not have to operate in a normal manner. That is, there may be no need to operate some of the lock's electronics, such as a credential sensing mechanism, during open conditions. Accordingly, electronic lock system power management strategies that take power needs during open and closed conditions into account would be advantageous.